Just got off the phone with David Ford from the FMCSA MIDWESTERN SERVICE CENTER (copy paste, didn't mean to scream it lol)
I asked him for clarification on Title 49 393.106(b) regarding load bars. He said if the trailer is 100% and/or is moved on property, it doesn't need need one. If it goes on the road and is less than 100% full, it needs one.
aka shifters don't need to be so anal retentive about load bars from a legal perspective. However, outbound drivers have the right to make sure their load (as long as it is less than 100%) has a load bar or strap.